fix a button stuck on cell phone?

1 button is stuck on my kyocera s1300. I accidently sat the phone in some hair gel a few weeks ago. At first about half the buttons were sticking, but now all of them work except for the upper righthand button at the very top. The button doesn't appear to be stuck down or anything, and when I push it nothing happens. Any ideas on how to get it to work again? I just got the phone about a month ago & don't really want to buy a new one over 1 button.